PROSITE documentation PDOC00131

recA family signature and profiles

The bacterial recA protein [1,2,3] is essential for homologous recombination and recombinational repair of DNA damage. RecA has many activities: it filaments, it binds to single- and double-stranded DNA, it binds and hydrolyzes ATP, it is also a recombinase and, finally, it interacts with lexA causing its activation and leading to its autocatalytic cleavage.

RecA is a protein of about 350 amino-acid residues. Its sequence is very well conserved [3,4,5] among eubacterial species. It is also found in the chloroplast of plants [6].

The recA protein is closely related to:

• Eukaryotic RAD51 protein. Promotes homologous pairing and strand exchange on chromatin.
• Eukaryotic DMC1 protein. Participates in meiotic recombination.
• Prokaryotic radA protein. Involved in DNA repair and in homologous recombination.
• Bacteriophage uvsX gene product. Important in genetic recombination, DNA repair, and replication.

As a signature pattern specific for the bacterial and chloroplastic recA protein, we selected the best conserved region, a nonapeptide located in the middle of the sequence and which is part of the monomer-monomer interface in a recA filament.

We also developed two profiles. The first one covers the ATP binding domain in the N-terminal part of the recA protein. The second one span the whole monomer-monomer interface. These two profiles also pick up the recA-like proteins.

roca@macc.wisc.edu.

           Eisen J.A.;
jeisen@leland.stanford.edu